A solid state drive (SSD) is a type of data storage device that uses solid state memory such as flash device to store data with high storage density. A SSD device may comprise a memory unit for storing data, and a management unit for reading data from and writing data to the memory unit. Accordingly, the SSD system requires a power supply for providing multi rails of power supplies to the multiple units.
As a power supply of a SSD system, when the power source at the input power terminal is interrupted or removed, the power supply is required to continue offering power to the SSD device for saving the data. One solution is to directly connect a bunch of storage capacitors at the input for providing energy when the power source is suddenly interrupted. In order to save the data safely, the hold up time should be long enough for saving relative data before the system is entirely off. Usually, a large amount of capacitors are used for storing enough energy, and the capacitors are discharged to a very low voltage for releasing the energy sufficiently. Thus, the capacitors will take up a large area on the circuit board and the cost is increased. Besides, in order to be adapted to the input voltage with a broad range, a buck-boost converter is required for supplying load and the efficiency of the system is low.
Accordingly, an improved power supply is desired to at least overcome part of the above mentioned deficiencies.